1. Field of the Invention
The present invention relates to a ramp toe system which is designed to retract a ramp toe of an aircraft ramp between a stored position contiguous with an outer surface of a ramp extension, and an extended position.
2. Description of Related Art
In the aircraft industry, a ramp is normally used to allow wheeled or tracked vehicles to drive on and off an aircraft to facilitate movement of cargo and other equipment. In order for the ramp to have proper strength and stability the end of the ramp needs to be fairly thick, usually about 8 to 10 inches. To bridge the height of the ramp end to the ground during loading or unloading, a ramp toe is needed, as shown in FIG. 1.
Previously, various types of conventional ramp toes have been used. FIG. 2 shows a pair of portable ramp toes. These ramp toes do not extend the entire width of the ramp, thus, making it difficult to align the vehicles upon the ramp toes while loading and unloading cargo. These ramp toes must be manually removed by the aircraft crew and stored inside the aircraft during flight.
Ramp toes that are hinged at the ramp often are stored above the ramp when not in use, as shown by U.S. Pat. No. 4,235,399 to Shorey and FIG. 3. This type of stowage is bulky, inconvenient, and prevents airdrop and parachute extraction of cargo. To alleviate problems, a stowage system can incorporate mechanisms to detach the toe from the ramp and stow the toe above the cargo door. Such a mechanism is shown in U.S. Pat. No. 4,140,291 to Evans et al., and in FIG. 3A. These systems require relatively heavy hardware and are difficult to maintain.
U.S.S.R. 265,726 discloses a ramp toe hinged on the end of a ramp and stored external to the aircraft's fuselage. Such an arrangement forces the ramp to be much longer, heavier, and cumbersome.
The improved ramp toe of the present invention is lightweight and extends the entire width of the ramp. The ramp toe retracts in such a way that it leaves the ramp surface and ramp end clear and operates conveniently; the ramp toe extends and retracts quickly without undue effort by the operator.
Advantages of the invention are set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.